Previously, the tubes of catheters and similar devices have been connected to other tubes by the use of two end pieces. One end piece was rigid and the other was flexible. The flexible end piece generally contained a female conical bore or hole while the other, or male, end piece had an outer conical shape which could be pressed into the conical bore. Since these types of tube couplings were not standard, the diameters, lengths and conical angles or tapers varied from manufacturer to manufacturer. Nevertheless, due to the elasticity of the flexible female conical member, end pieces with various different dimensions could be used. There was, however, a substantial danger with such connections that they would unintentionally separate.
It is of particular importance for safety that accidental disconnection of joined tubes not take place when bladder catheters are used in urine collecting systems. Because of tension applied to tubes by restless and careless patients, unintended separation of the tube connection occurs, urine leaks out and the connection is contaminated with bacteria. Investigations have established that contamination of the connection location is a main cause of urinary duct infections. Therefore, because of the great danger of contamination, the hose connection should not be separable or disconnectable, not even by the nursing personnel. A need accordingly exists for a tube coupling for medicinal purposes where unintended disconnection, even under severe tension or pulling, is prevented.